长江流域田间配置对玉米-大豆带状复合种植群体产量和气候资源利用效率的影响

Effects of Field Configuration on Yield and Climate Resource Utilization Efficiency of Maize-Soybean Strip Intercropping in the Yangtze River Basin

【目的】探究长江流域各地区群体产量效益与光、温、水资源利用效率最优的生产单元和行比配置。【方法】在长江流域粮食主产区,以当地主栽的带状复合种植模式为主,四川与湖北地区采用春玉米夏大豆带状套作模式,湖南与江西地区采用春玉米春大豆带状间作模式,江苏地区采用鲜食玉米鲜食大豆带状套作模式,以单作玉米(MM)与单作大豆(SS)为对照,设置5个不同的玉米-大豆带状间套作田间配置:生产单元2 m行比2∶2(T1)、生产单元2.4 m行比2∶3 (T2)、生产单元2.4 m行比2∶4 (T3)、生产单元2.8 m行比2∶3 (T4)、生产单元2.8 m行比2∶4 (T5)。【结果】3年试验结果表明各地区玉米产量总体呈现随生产单元宽度增加下降的趋势,大豆产量呈现为相反趋势,群体产量呈现随生产单元宽度增加下降的趋势。不同区域玉米-大豆带状复合种植均表现出明显的间套作优势,土地当量比在不同地区之间尤以长江上游的四川、湖北生态区表现突出,最高达1.64。长江上中下游各田间配置群体产量效益与光温水资源利用均大幅高于单作大豆,在生产单元2 m,行比2∶2的田间配置下相较单作玉米,长江上游四川与湖北试验点平均经济效益分别提高了39.20%、39.34%,光温水生产效率分别提高了31.48%、19.42%、13.85%(四川)和56.90%、41.45%、42.89%(湖北),长江下游江苏试验点3年平均经济效益提高22.22%,光温水生产效率分别提高22.09%、13.16%、14.41%。长江中游湖南试验点在生产单元2.4 m,行比2∶3的田间配置下3年平均经济效益与光温水生产效率较单作玉米分别提高13.07%、13.86%、7.77%和6.45%,长江中游江西试验点在生产单元2.4 m,行比2∶4的田间配置下3年平均经济效益与光温水生产效率较单作玉米无显著差异。【结论】综合3年群体产量效益与资源利用率及主成分分析表明,长江上游(四川、湖北)与长江下游(江苏)玉米-大豆带状套作区应实行生产单元2 m,行比2∶2的田间配置,长江中游(湖南、江西)带状间作区可分别采用生产单元2.4 m,行比2∶3与生产单元2.4 m,行比2∶4的田间配置。

【Objective】The objective of this study was to explore the optimal production unit and row ra-tio allocation for maximizing population yield benefit and the utilization efficiency of light,temperature,and water resources in various regions of the Yangtze River Basin.【Method】Conducted in the main grain-producing areas of the Yangtze River Basin,this study primarily focused on the local main banded composite planting mode.The Sichuan and Hubei regions adopted a banded intercropping mode of spring maize and summer soybean,the Hunan and Jiangxi regions adopted a banded intercropping mode of spring maize and spring soybean,and the Jiangsu region adopted a banded intercropping mode of sweet corn and soybean.Monoculture maize(MM)and monoculture soybean(SS)served as controls.Five dif-ferent maize-soybean strip intercropping field configurations were established:production unit 2 m with line ratio 2∶2(T1),2.4 m with line ratio 2∶3(T2),2.4 m with line ratio 2∶4(T3),2.8 m with line ratio 2∶3(T4),and 2.8 m with line ratio 2∶4(T5).【Result】The three-year experimental results indicated that maize yield in each region generally showed a downward trend with the increase in the width of the production unit,while soybean yield showed an opposite trend.The population yield also showed a down-ward trend with the increase in the width of the production unit.Maize-soybean strip intercropping in dif-ferent regions exhibited clear intercropping advantages,with the land equivalent ratio being particularly outstanding in the Sichuan and Hubei ecological areas of the upper Yangtze River,reaching a maximum of 1.64.The yield benefit and utilization of light,temperature,and water resources for each field configu-ration group in the upper,middle,and lower reaches of the Yangtze River were significantly higher than those of monoculture soybean.Under the 2 m production unit and 2∶2 row ratio field configuration,com-pared with monoculture maize,the average economic benefits of the Sichuan and Hubei experimental sites in the upper reaches of the Yangtze River increased by 39.20%and 39.34%,respectively.The pro-duction efficiency of light,temperature,and water increased by 31.48%,19.42%,13.85%(Sichuan)and 56.90%,41.45%,42.89%(Hubei),respectively.The average economic benefits of the Jiangsu ex-perimental sites in the lower reaches of the Yangtze River increased by 22.22%,and the production effi-ciency of light,temperature,and water increased by 22.09%,13.16%and 14.41%,respectively.In the middle reaches of the Yangtze River,under the 2.4 m production unit and 2∶3 row ratio field configura-tion,the average economic benefit and the production efficiency of light,temperature,and water in the Hunan test site were 13.07%,13.86%and 7.77%higher than those of monoculture maize.In the Jiangxi test site,under the 2.4 m production unit and 2∶4 row ratio field configuration,the average economic benefit and the production efficiency of light,temperature,and water were not significantly different from those of monoculture maize.【Conclusion】Based on three-year population yield benefit,resource utilization rate,and principal component analysis,the maize-soybean relay strip intercropping areas in the upper reaches of the Yangtze River(Sichuan,Hubei)and the lower reaches(Jiangsu)should imple-ment the field configuration of a 2 m production unit with a 2∶2 row ratio.In the middle reaches of the Yangtze River(Hunan,Jiangxi),the field configurations of a 2.4 m production unit with a 2∶3 row ratio and a 2.4 m production unit with a 2∶4 row ratio can be used,respectively.